FIELD NOTE
Growth and Survival of Port-Orford-Cedar Families
on Three Sites on the South Oregon Coast
ABSTRACT
Constance A. Harrington, Peter J. Gould, and Richard A. Sniezko
Port-Orford-cedar is of interest to ecologists and foresters, but little information is available on its growth, its genetic variation, or the field performance of
families selected for resistance to root disease. Survival, damaging agents, and growth were evaluated for nine families at three outplanting sites in south coastal
Oregon. Survival was excellent on two sites. Family differences were observed in growth rates, foliage dieback, and tendency to form multiple stems after
browsing. Mean tree height 8 growing seasons after planting was 2.6 m; the heights of the tallest trees on one site were >5.5 m.
Keywords: Chamaecyparis lawsoniana, Phytophthora lateralis, multiple stems, browsing damage, foliage disease
P
ort-Orford-cedar (Chamaecyparis lawsoniana) has a narrow
native range (in northern California and southern Oregon;
Zobel 1990), but as an ornamental, it has been widely planted
on several continents. The wood of the species is quite valuable, but
introduction of a nonnative root rot, Phytophthora lateralis, has re­
sulted in substantial mortality within its native range, and many
managers have considered it not to be a suitable candidate for refor­
estation because of this disease. The US Forest Service and Bureau of
Land Management have established a program at the Dorena Genetic
Resource Center (Dorena GRC) to screen for genetic resistance to
Port-Orford-cedar root disease; this program oversees breeding to pro­
duce resistant seed for reforestation and restoration (Sniezko 2006). In
2002, three outplanting sites were established by the Dorena GRC with
forest industry cooperators to evaluate the growth and disease resistance
of 9 families from this program. This report covers growth, survival, and
damage for those sites through plantation age 8.
Materials and Methods
Seed from the disease resistance program at Dorena GRC was
used in this study. The parent trees originated from natural stands
and are represented as rooted cuttings in orchards or clone banks at
Dorena GRC. Some seedlots used in this trial were full siblings from
controlled crosses, and others were the result of wind pollination
among many parents in the containerized orchards. The nine seedlots (families) were chosen to cover the full range of mortality (from
0 to 100%), which resulted from a seedling root-dip test using P.
lateralis in a greenhouse trial (R. Sniezko, unpublished results). Six
families had maternal parents from low elevation (<800 m) areas in
the south Oregon coast (JR13 Breeding Zones 110, 125, and 210;
see Dorena GRC 2006 for breeding zones), and three families had
maternal parents from higher elevation (>800 or >1,200 m) areas
more inland in southern Oregon or northern California (JR13
Breeding Zones 350, 440, and 450). Seedlings were grown in
164-mL containers at Dorena GRC for 1 year.
The outplanting locations (Table 1) were in Coos County, Or­
egon (one site 8 km northeast of Bandon), and Curry County,
Oregon (two sites 16 –22 km east of Sixes). The surface soil texture
at all locations was silt loam. Port-Orford-cedar had been present in
the previous stands at all sites, but root disease had not been docu­
mented. Port-Orford-cedar root disease spreads by movement of
spores in water or soil (attached to animal feet or equipment) or by
transport of diseased stock. At each outplanting location, four
blocks were established. Families were randomly assigned to rows
in each block, with 8 –10 seedlings per family in each block. The
planting locations were viewed prior to planting; areas consid­
ered unsuitable for planting (e.g., old skid road or large stump)
were skipped, and the row was extended as necessary to plant all
the seedlings. Site preparation treatments were applied prior to
planting; photographs taken shortly after planting provided ev­
idence that competing vegetation was well controlled at all sites
at that time. Disease-free seedlings were outplanted by hand in
spring 2002.
After outplanting, the sites were visited periodically and surveyed
for mortality (causes ascertained in most cases by pathologists) and
other damage. Trees were measured for height 4 growing seasons
after outplanting and for height and diameter (at 1.3 m) 8 growing
seasons after outplanting.
Results
Survival and Damage
Survival was excellent at the Tent Prairie (99%) and Coquille
River (97%) outplanting sites, with most trees in all families surviv­
ing to the 8-year evaluation. Survival was much lower (60%) at the
Manuscript received April 11, 2011, accepted August 3, 2011. http://dx.doi.org/10.5849/wjaf.11-015.
Constance A. Harrington (charrington@fs.fed.us), and Peter J. Gould (pgould@fs.fed.us), US Forest Service, Pacific Northwest Research Station, Forestry Sciences Laboratory, 3625 93rd Avenue
SW, Olympia, WA 98512-9193. Peter J. Gould and Richard A. Sniezko (rsniezko@fs.fed.us), US Forest Service, Dorena Genetic Resource Center, 34963 Shoreview Road, Cottage Grove, OR
97424. We thank the Menasha Corporation, Moore Mill Company, and Plum Creek Timber Company for installing the plantings and allowing access for ongoing assessments and Oregon State
University for their ongoing assistance in the pathology evaluations and the resistance breeding work. We also thank the other employees and volunteers who have participated in the assessments.
Readers interested in participating in future trials of Port-Orford-cedar should contact Richard Sniezko.
This article uses metric units; the applicable conversion factors are: centimeters (cm): 1 cm = 0.39 in.; meters (m): 1 m = 3.3 ft; kilometers (km): 1 km = 0.6 mi; milliliter
(mL): 1 mL = 0.061 in.3 (dry), = 0.27 fluid dram (liquid).
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WEST. J. APPL. FOR. 27(3) 2012
Table 1.
Site information for 2002 Port-Orford-cedar outplantings.
Site name
Cooperator
Soil mapping unita
Drainage class
Elevation
(m)
Slope
Browse
control
Tent Prairie
Moore Mill
Moderately well
577
10%–20%
Vexar tubes
Coquille River
Avery Ranch
Menasha
Plum Creek
Etelka-WhobreyRemote
Templeton
McCurdy-Wintley
complex
Well
Moderately well
20
153
Mostly flat
Mostly flat
Fence
Fence
a
b
Mean
minimum
temperature,
coldest
monthb
Mean
maximum
temperature,
warmest
monthb
Mean April–
September
precipitationb
(mm)
. . . . . . . .(°C) . . . . . . . .
1.8
22.6
3.1
2.4
347
21.9
24.9
326
334
Based on USDA Natural Resource Conservation Service 2011.
Climate information from the Rocky Mountain Research Station Climate Model 2011.
Table 2. Mean (with standard deviation), minimum (min), and maximum (max) heights and diameters of Port-Orford-cedar families 8
years after outplanting at three sites.
Height (m)
Tent Prairie
Family
Mean
(SD)
15
17
34
36
39
41
42
43
44
2.1 (0.38)
2.4 (0.39)
2.2 (0.37)
2.7 (0.37)
1.9 (0.37)
1.7 (0.38)
2.2 (0.37)
2.2 (0.38)
2.0 (0.39)
Coquille River
Min Max
1.1
0.8
0.9
1.2
0.8
0.8
1.3
0.7
0.6
dbh (cm)
2.9
3.4
2.9
3.6
2.6
2.5
3.0
2.8
3.2
Mean
(SD)
2.0 (0.38)
2.6 (0.40)
2.6 (0.41)
2.4 (0.40)
2.7 (0.39)
2.9 (0.39)
2.3 (0.39)
2.4 (0.39)
2.0 (0.40)
Avery Ranch
Min Max
1.2
0.8
0.8
1.1
1.4
1.2
0.7
0.8
0.9
3.9
4.3
4.3
4.9
4.0
4.2
3.3
4.4
3.8
Mean
(SD)
3.6 (0.42)
4.3 (0.42)
3.9 (0.43)
3.8 (0.44)
3.7 (0.43)
4.1 (0.51)
3.5 (0.42)
3.9 (0.44)
2.8 (0.48)
Tent Prairie
Min Max
1.5
3.0
2.2
2.2
2.9
2.9
2.3
3.0
1.0
Avery Ranch site. Some trees were dead by the end of the first or
second growing season; additional mortality was coded at each visit
to Avery Ranch. Approximately 40% of the trees at Avery Ranch
had vole damage, and voles were the primary mortality agent at this
site. Very few tree deaths were attributed to P. lateralis. Evidence of
bark beetle activity (probably Phleosinus spp.) was also observed on
some trees. Stigmina foliar blight and cypress or Seiridum canker
were each observed on one tree.
The sites differed in the major damaging agents. The unfenced
Tent Prairie site was heavily browsed by deer and elk in early years
(>90% of trees were coded as browsed 4 years after outplanting);
most of the formerly browsed trees recovered well, and their termi­
nals are now above likely height for future browsing. Past browsing
resulted in 23% of the trees forked below 1.3 m and about 10% with
two or more leaders at the 8-year measurement. Forking occurred in
some trees in all families but was most prevalent on families 17
(50%) and 42 (37%). Coquille River had 31% of the surviving trees
with foliage dieback at the 8-year measurement; this condition ap­
peared on only 11% of trees in families 17 and 41 and on 260% of
surviving trees in families 42, 43, and 46 (these three families were
from the more inland breeding zones).
Height and Diameter
Individual tree heights 4 growing seasons after planting ranged
from 45 to 305 cm (Table 2). Heights after 8 growing seasons
ranged from 55 to 600 cm. Mean tree height after year 8 (Figure 1)
was least at Tent Prairie (2.2 m), intermediate at Coquille River (2.4
m), and greatest at Avery Ranch (3.7 m). Family rankings were
generally consistent, especially for the 2 fenced sites. With one ex­
ception (family 46), mean height after 8 growing seasons was 2 m or
greater for all families at Coquille River and >3.5 m tall at Avery Ranch.
4.2
6.0
4.9
4.8
4.7
5.2
4.7
5.5
4.1
Mean
(SD)
2.1 (1.19)
3.0 (1.56)
2.3 (1.29)
3.8 (1.47)
1.4 (1.03)
1.0 (0.96)
2.4 (1.29)
2.5 (1.46)
2.0 (1.66)
Coquille River
Min Max
0.2
0.3
0.6
1.1
0.2
0.1
0.1
0.2
0.2
4.6
6.0
5.0
8.5
4.1
3.0
4.4
5.8
6.6
Mean
(SD)
Avery Ranch
Min Max
1.6 (1.36)
2.6 (1.80)
2.7 (1.96)
2.4 (1.92)
2.8 (1.37)
3.1 (1.57)
2.1 (1.19)
2.3 (1.69)
1.6 (1.78)
0.1
0.1
0.1
0.2
0.3
0.4
0.1
0.2
0.1
5.5
7.5
7.9
9.2
5.6
6.5
4.8
8.4
6.6
Mean
(SD)
4.6 (1.77)
6.5 (2.40)
5.0 (2.42)
5.1 (2.33)
5.1 (1.80)
5.9 (2.63)
4.5 (2.74)
6.3 (2.49)
3.1 (1.77)
Min Max
0.1
1.8
1.3
0.1
1.5
1.9
0.4
2.9
0.2
7.5
11.6
9.6
8.4
8.0
10.8
9.9
11.3
6.5
The tallest family at each site was also the one with the greatest
diameter at 1.3 m (Table 2). Overall, after 8 growing seasons, the
best families at Tent Prairie and Coquille River had mean diameters
>3 cm, and the best families at Avery Ranch had diameters >6 cm.
There were not enough representatives of each breeding zone to
test for differences in growth between zones. There were three fam­
ilies with the same maternal parent (families 15, 17, and 36); the
poorest performer of these three families was 15, which was selfed
(fertilized with pollen collected from the same clone). The other
family that tended to be a poor performer in height was family 46,
whose maternal parent was from a high-elevation (>1,220 m)
breeding zone.
Discussion
There is very little information in the literature on Port-Orford­
cedar regeneration in a forest setting (as opposed to use as an orna­
mental), and what has been published has generally been negative or
cautionary because of root disease (Zobel 1990), concerns over cold
hardiness (Duffield 1956, Hunt and Dimock 1957), or poor sur­
vival after outplanting (Kitzmiller 2006). However, foresters and
ecologists have become interested in using the species for reforesta­
tion to further ecological goals of preserving species diversity (sub­
stantial mortality has occurred within its native range) or timber
production goals (valuable wood, not susceptible to Swiss needle
cast disease). Although several Port-Orford-cedar plantations have
been established in recent years, to our knowledge, this is the first
report of outplanting performance of multiple families at several
sites in the Oregon Coast Range. These outplantings demonstrate
our ability to regenerate Port-Orford-cedar. It will take longer than
8 years to evaluate the sensitivity of these outplantings to the full
range of damaging agents and to express their full growth potential.
WEST. J. APPL. FOR. 27(3) 2012
157
Figure 1. Mean height and standard error for all surviving trees 8 years after outplanting of Port-Orford-cedar families by outplanting site and
family. Standard errors were calculated from individual tree values for each site and family. Percentage of mortality is indicated by the number
at the top of each bar. Root rating indicates whether the family had high (H), medium (M), or low (L) survival based on a seedling root-dip test
with Phytophthora lateralis. The shaded bars indicate maternal parents from inland breeding blocks (Dorena Genetic Resource Center 2006).
Some Early Lessons Learned From the Plantings
The species can survive well after outplanting, but it is susceptible to several damaging agents. In previous outplantings in California and Oregon (Kitzmiller 2006), two of five sites were dropped
from the study early on because of poor survival associated with lack
of vegetation control, and by year 7, survival of the remaining outplantings ranged from 34% to about 77%. Thus, we are encouraged
by the high survival rate on two of our sites.
At the Coquille River site, where foliage dieback was common,
the three families from more inland sources were much more susceptible than the families from more coastal sources. The foliage dieback observed on nonlocal sources at this coastal site may be important,
especially if harvesting boughs is being considered as an option.
At the unfenced Tent Prairie site, families differed substantially in
the percentage with forking below 1.3 m, so we would suggest that
forking be coded in future evaluations of outplantings. Vole damage
was a factor at the Avery Ranch site, so controlling grassy or herbaceous
vegetation may be important in getting seedlings established (Duddles
and DeCalesta 1992). Animal damage at these sites confounded the
usual relationship between good growth and good survival seen when
physical factors such as soil moisture are controlling plant responses.
Port-Orford-cedar root disease has not played a major role in
mortality to date; therefore, we cannot yet tell whether the rankings
of resistance based on seedling root dips will be effective in predicting family resistance in the field until information is available for a
longer time period or from more families and sites. It was notable,
however, that P. lateralis was not a major source of mortality
through age 8. On the basis of our results, other outplantings in
progress, and general ecophysiological information (e.g., Zobel
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WEST. J. APPL. FOR. 27(3) 2012
1990), we suspect that additional successful outplantings could be
made if the following guidelines were followed: obtain seed from the
Dorena GRC resistance program, select seedlots from appropriate
breeding zones, plant seedlings on sites that are not compacted or
poorly drained, and control competing vegetation during
establishment.
Literature Cited
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